Ocean waves occur through conversion of part of the wind energy across ocean areas. The wave energy calculated per surface area is essentially greater than the solar and wind energy in the same area. Utilization of wave energy from the ocean therefore constitutes an almost inexhaustible, renewable source of energy, and it is the only pure energy source which may potentially replace today's consumption of fossil fuels.
On the basis of the above-mentioned conditions, solutions for the utilization wave power have been proposed over the last decades. Large-scale and full scale wave power stations have also been built in many embodiments, without any of the projects having provided the desired result.
A wave power station based on the wedge chute principle stand out as a simple and reliable plant. Simplified the system may be explained as the incoming waves being forced inwards between the two cuneiform side edges, whereby the maximum height of the waves increases. At the narrowest end portion of the wedge, at a level above the sea surface is arranged a collecting basin. Wave crests exceeding this level, flow over the edge of the basin and fill the basin. The drop of the water between the collecting basin and sea level is utilized in a conventional manner by means of a low-pressure turbine.
The reason why wave power stations of this kind are not used to a great degree is, i.a., that a relatively small efficiency is achieved in practice. One of the reasons for this is that if a wave comes in, which does not reach all the way up to the edge of the basin, the water of this wave will return within the wedge, in which it may possibly break an entering wave which would be large enough to reach into the basin. Another reason is that when a really big wave comes, considerably exceeding the height of the basin, part of the energy of the wave will not be utilized because the water will drop to the relatively low predetermined basin height. The two conditions mentioned contribute to the fact that wave power stations based on the wedge chute principle have an efficiency in the order of 15%.
It has turned out to be difficult to size wave power stations according to other known technique so that they have sufficient strength to withstand the forces arising in an environment of the kind in question.